J. J. Watt eats a lot of fat. Yes, the laser-focused training machine known as J. J. Watt—a man who spends every waking moment trying to make himself the best athlete possible—includes healthy portions of fat in his diet. Why? Because he has to.

In a recent ESPN.com article, Watt talked about some major changes he's made to his diet over the last few months. The driving force behind the changes can be traced to Watt's winter workouts. He was feeling sluggish and out of it, even though he thought he was doing everything right.

Then Watt discovered he was woefully lacking in calories. He needed roughly 9,000 calories a day to properly fuel his activity, significantly more than he was consuming at the time. To get that many calories, Watt had to change the way he thought about food. He learned fat can be his friend, a nutritional principle many young athletes could benefit from. Here's why.

Calories are King

The reason Watt felt cruddy during his winter workouts is simple—he wasn't consuming enough calories. Calories are the measure of the energy we get from the foods we eat. Without calories, our bodies cannot function. Generally speaking, the more active you are, the more calories you need—so a guy like Watt, who seemingly never stops working out, needs a ton of calories.

When your calories fall significantly short of what your activity level requires, fatigue and impaired focus can result—even if you're in insane shape, as is Watt. In fact, Watt's lean, muscular build probably exacerbated the issue. It meant he had very little spare body fat to burn and convert to energy, which is what typically happens when one is in a calorie deficit.

Why did Watt have a deficit in the first place? He was probably being too obsessive about the way he ate. He wanted all his food prepared in the "healthiest way" possible, and he generally stayed away from high-fat foods. That approach makes sense for an overweight couch potato, but it did not make sense for Watt. It actually doesn't make sense for many athletes.

"The popular thing of the day is 'eating clean.' And what that generally refers to is eating meats, veggies and fruit, and everything is grilled and nothing is prepared with oil. And that really isn't good for many football players," says Roberta Anding, Director of Sports Nutrition at the Houston Children's Hospital and former dietitian for the Houston Texans. "These concepts of 'eating clean' and eating low-fat may run contrary to sports nutrition science."

Since Watt is incredibly dedicated, he had stuck to the lean diet to a T. The end result was that he came up woefully short on calories.

"Watt and athletes like him have an unbelievable work ethic and determination," Anding says. "And sometimes they'll be given a little bit of nutritional information, but not all of it. He was told lean is the way to go and he stuck to it. But at some point in time, it came back and bit him in the behind. He needed more calories."

Handful of Nuts vs. a Truckload of Broccoli

In an effort to add more calories to his diet, Watt began eating more high-fat foods—things like avocados, bacon, oils and fatty fish such as salmon. You might be thinking to yourself, "why did Watt have to eat high-fat foods? Couldn't he just load up even more on lean meats and vegetables?"

In theory, maybe. But in reality, no way. The low-calorie nature of many vegetables and lean meats would've made it nearly impossible for Watt to meet his calorie requirements.

"If you do the math, you just can't make up the extra calories with something like broccoli," Anding says. "Broccoli is only 25 calories per cup. Compare that with a high-fat food like nuts. Nuts are about 600 calories per cup, and 70 percent of those calories come from fats."

It's a struggle for Watt to meet his calorie requirement even when he includes high-fat foods. Without them, it would be downright impossible. "Let's say you try to get those extra calories through pineapple or broccoli or grilled chicken. The volume of food you would have to eat is prohibitive. It's too much," Anding says.

When Anding was with the Texans, she used high-fat foods to help players meet their calorie requirements. "We had two buffet lines, one for the players who had excess body fat and one for the players who were lean. The foods were similar, but for the lean guys, we prepared the food in a way that would add more calories. We might've cooked it with more oil or added nuts to it," Anding says.

Many athletes fall into the same trap Watt did—they try to eat too lean and they simply don't get enough calories because of it. "I had a rookie who came onto the Texans, and in college all he ate for lunch was tunafish with no mayo and egg whites. And I told him, 'you're not going to make it in the NFL eating like that.' So I told him to eat things like avocado and oils and nuts, because those are high-fat, high-calorie foods," Anding says.

The Protein Defender

Calories aren't the only reason fat is important in an athlete's diet. Although carbohydrates are the main source of fuel for exercising bodies, fat can be used as well. "Depending on the intensity, fat can be used as an energy source," Anding says. This fact has a significant effect on the way our bodies handle protein.

Many people think of building muscle in simple terms—eat more protein, make more muscle. But this isn't the case. Anding says, "When it comes to muscle protein synthesis, it isn't arithmetic, it's calculus. There's a lot more variables involved. You have to have protein bodyguards, which are carbohydrates and fat." If you aren't consuming enough calories, your body will burn protein as an energy source. This means the protein cannot serve the purpose it was meant for—building and repairing muscle.

"If you have enough calories, your body will use protein to burn and repair muscle," Anding says. "If you don't, it will use protein as an energy source. You don't want to use it for that. Protein is a very expensive energy fuel that should be used for something else."

Including certain high-fat foods in your diet can help ensure you won't come up short on calories and you'll let protein do what it is intended to do.

Friendly Fats

Although high-fat foods can help you reach your caloric goal, they aren't all created equal. You want to look for foods that are naturally high in fat, especially plant-based ones. "Focus on things like nuts, healthy oils, seeds, avocados. There's a big difference between an avocado and a pork rind. They're both high-fat foods, but one comes from a plant and has lots of other useful natural compounds. The other is just animal fat," Anding says.

Cooking with healthy oils (such as olive, peanut and coconut) is another great way to increase your calories. Nuts and seeds are tasty and high in fat, and they can easily be added to other foods to raise your calorie count—like adding a tablespoon of flaxseed to your oatmeal). Salmon contains healthy fats. Pesto is an olive-oil based sauce that typically contains pine nuts and a little cheese, and its flavor makes it a versatile way to add extra calories to different foods.

When Anding was with the Texans, the team kept a gigantic 55-gallon drum of trail mix in their training room so the lean players could scoop it up on their way out and eat it as a snack. Trail mix makes for a tasty and easy high-fat, high-calorie snack. "Trail mix is a great snack for between classes," Anding says.

Some occasional animal fat is OK in your diet, but don't go crazy with it. "You can have animal fat, just don't overdo it. Don't put a bunch of butter and cream gravy and cheese on everything," Anding says.

Using healthy oils can be a great way to prepare your favorite foods without sacrificing flavor or calories. Take French Fries for example. Anding says, "If they're prepared in the oven and basted with olive oil, that's awesome. But if you're going to a fast food restaurant, that's not so good."

Brandon Hall
- Brandon Hall is an Assistant Content Director for STACK. He graduated from Lafayette College, where he played football and graduated with a Bachelor's degree in English.
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